The message begins with the text 'The database did not find the text of a page that it should have found, named "$1".'. But parameter $1 is not only the name of a page, it also includes a page revision number or the revision numbers for a diff. That means that the text inside the quotation marks is "Pagename (revision#: 123)". It would be nice if it was possible to have only the name inside the quotes, like '"Pagename" (revision#: 123)'.
Maybe the message can be changed to begin with 'The database did not find the text of a page that it should have found, named "$1" $2.', where $1 is only the page name and $2 is the version numbers formatted as in the messages 'missingarticle-rev' and 'missingarticle-diff'.